i lost my world

i was casualy playing minecraft  i saved my world closed the game... next day i opened minecraft pressed play and my world wasnt there so i checked my folder and my world was there but it had no level.txt text in it it was empty same as level.txt old but te files were there so i tried to fix it by copying the files to the folder but it didnt worked so i tried to import it by remaking the world into .mcworld but that also didnt worked so i dont know what to do anymore could you help me btw 1.17.10 does really have bug with deleting world my friend work has been deleted too 

 

 

Heres my world